512 JOSEPH STAFFORD, 



siderable numbers and at no great distance from one another ; and in 

 fact I have found as many as twenty in the field of view of the oil- 

 immersion system, by slightly focussing. The number 1944 I regard 

 as normal, but I am fully prepared to believe that there are, in many 

 animals, deviations from this number. Occasionally one finds in the 

 branching of the smaller vessels similar irregularities to those I have 

 already pointed out in the first division of the left system where one 

 of the three twigs is a little removed from the other two. Rarely 

 occur cases where only two branches are present and then , if there 

 is a difference of size, they appear as a single twig leaving its parent 

 stem. But I have learned to be very deliberate in accepting such 

 cases. Many times I have found one branch obscured for a short 

 distance by another overlying it, or the pressure happened to be so 

 great at that particular place as to obliterate a portion of one. To 

 avoid such accidents I have made use of my highest dry system of 

 lenses and used preparations enclosed only on two sides of the cover 

 glass, so that, by running a drop of water to the edge, I could relieve 

 the pressure and cause a slight change in the position of the animal. 



In one animal I have lately seen the right main stem, after giving 

 off its neck branch, divide into two — a smaller which gave three 

 divisions, and a larger which bent backwards and downwards for a 

 short distance and gave off" four divisions of which one ran forwards 

 and towards the foot, one posteriorly, and the two middle divisions 

 were distributed to the region of ovary and testis. In the same 

 animal the left system gave off' an anterior branch and soon after the 

 main stem divided normally into three of which two went backwards 

 and one to the genital organs. In another animal the right system 

 was found to divide primarily into four instead of three, two anterior, 

 one inferior and one posterior. 



While the three connate branches of a larger trunk generally 

 preserve a similarity in size and length yet sometimes one or two of 

 them may be longer than the third permitting the funnels to reach 

 regions where perhaps no others are present. I have seen capillaries 

 of the same group with dificrent lengths. 



VoELTZKOw and Huxley both thought that the genital glands 

 were supplied from the left system. This conclusion was of course 

 built on the direction of the larger more visible branches. From 

 what I have said it will be evident that branches from the right side 

 also come in close proximity to these organs. One can not from this, 

 however, draw the conclusion that their end organs lie close round 



